Do you have juice yet? If not, go to the forum suppliers and pick one out. My favorite at the moment is Vapor 4 Life. Filling the cart is super easy. All you do is slowly drip drops into the empty filler until it quits absorbing. Some carts you can even pull the filler out and put drops in the bottom of the cart to speed to process up, then replace it and continue filling until it looks full. After you do this a couple of times you'll get the hang of it. Also, drip a drop or two directly on the bridge(microphone looking thing) to prime the atomizer. This aids in helping wick the juice from the cart to the atty's heating element. Good luck!!